An experimental nuclear fusion reactor is designed to produce a net electrical power output of 540 MW540\text{ MW}540 MW using a helium-3 fuel cycle. In this reactor, each fusion reaction has an associated mass defect of 0.018 u0.018\text{ u}0.018 u. The overall thermodynamic efficiency of converting the released fusion energy into electrical power is 45%. How many fusion reactions must occur per second to sustain this power output?
(Use: 1 u=1.66×10−27 kg1\text{ u} = 1.66 \times 10^{-27}\text{ kg}1 u=1.66×10−27 kg, c=3.00×108 m s−1c = 3.00 \times 10^8\text{ m s}^{-1}c=3.00×108 m s−1)
9.0×10199.0 \times 10^{19}9.0×1019
2.0×10202.0 \times 10^{20}2.0×1020
4.5×10204.5 \times 10^{20}4.5×1020
1.3×10291.3 \times 10^{29}1.3×1029
128 exam-style questions on AQA A Level Physics Radioactivity (A-level only), covering Rutherford scattering (A-level only), $\alpha$ , $\beta$ and $\gamma$ radiation (A-level only), Radioactive decay (A-level only), Nuclear instability (A-level only), Nuclear radius (A-level only), Mass and energy (A-level only), Induced fission (A-level only), and Safety aspects (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.